Map.computeIfAbsent: Write a clear and concise code

Table of ContentsHow?Method SignatureBehaviourTest Your KnowledgeReferences How? Suppose you are solving a graph problem where you have been given a 2D array of edges and you need to find the shortest path between a source and a destination node. At this point, you could create a graph from the given edges. ... public List<Integer> findShortestPath(int[][] ...

How to deploy Step functions composed of 3 Lambdas using AWS CDK (Typescript)

Table of ContentsInstall and configure packagesSetup LambdasDeploy and TestReferences Install and configure packages 1. Install and Configure the AWS CLI by following the steps mentioned in the below link https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-quickstart.html#cli-configure-quickstart-config 2. Install NodeJS by the following the instructions in the following link https://nodejs.org/en/ 3. Install the AWS CDK by running the following command npm install ...

Enforce TLSv1.2 on Nginx and CloudFlare

Enforce TLSv1.2 on Nginx and CloudFlare
Table of ContentsBefore ConfigurationConfigure TLSv1.2 on your NginxEdit the Nginx config filesEdit nginx.conf fileEdit server block configuration fileUpdate Cloudflare SSL/ TLS configuration for minimum TLS versionWhy the hassle?After Configuration Does SSL-Labs test for HTTPS assessing your site as ‘B’ grade? Is it complaining that your server still supports TLSv1.0 (Transport Layer Security protocol) and TLSv1.1? ...

AWS Outposts

AWS Outposts is a hybrid cloud service offered by Amazon Web Services (AWS) that allows customers to run AWS infrastructure and services on-premises. AWS Outposts provides the same hardware and infrastructure that is used in AWS data centers, and the same software, APIs, and tools that customers use in the cloud, making it easy for ...

AWS S3 object level file integrity

AWS S3 object-level file integrity verification is a feature of Amazon S3 that provides a mechanism for verifying the integrity of objects stored in S3. The feature is useful for ensuring that data stored in S3 is accurate and complete, even if the data is transferred over a network or stored in S3 for an ...

Durability in Databases

Durability is the process of persisting the writes that clients make to the database to a non-volatile storage disk. Caveat is that the writes should also be committed. This means once the commit has succeeded and right after that our system loses power or the system crashes and we need to restart, then our changes ...

Transaction Isolation

Transaction Isolation
The third of ACID properties “Isolation” is basically the question: “Can an in-progress transaction see changes made by another transaction running in-parallel?” Follow up to it would be “If yes, at what point of time can it see such changes?” Let’s try to analyse some aspects of the above question(s) from the db system implementation ...

Consistency in Databases

Consistency in Databases
It is one of the ACID properties which is often traded-off between different database systems (relational/ nosql/ graph etc.) (heard of eventually consistent DB?). It is often sacrificed for speed, scalability in some databases It can be categorised in two parts: Consistency in DataConsistency in Read Data Consistency That a transaction leaves the updated database ...

Atomicity

Atomicity is one of the four ACID properties that define a database system. While ACID properties are usually referenced in Relational DBMS, they are still an applicable concept for nearly any database system out there. Let’s see what it is… All queries in a transaction must succeed. Like an atom (something which can’t be split)If ...

Database Transaction

Database Transaction
In this article we discuss about what is a Database Transaction, what are its intricacies and why it’s needed? A transaction is simply “a collection of SQL queries which are treated as a single unit of work.“ What is the need of a db transaction? Let’s think about the scenario where transactions were not possible, ...